OpenSSL Tutorials

In this section you will find our OpenSSL guides: installing OpenSSL on Windows and on Ubuntu, checking which version you are running, generating a self-signed certificate, and checking when a certificate expires.

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How to Install OpenSSL on Windows

Windows does not include OpenSSL, so you have to install it yourself. This guide covers picking the right build, running the installer, adding OpenSSL to your PATH so the command works in any terminal, and fixing the errors that usually show up straight after installation.

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How to Install OpenSSL on Ubuntu

Most Ubuntu systems already have OpenSSL, but not always the version you need. This guide covers all three routes: installing with apt, compiling a specific version from source, and running OpenSSL in a Docker container, along with how to confirm which one you ended up with.

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How to Check the OpenSSL Version on Linux, Windows, and Mac

The openssl version command tells you what you are running, but its one-line output leaves out details you often need, such as the build date and the directory OpenSSL reads its configuration and certificates from. This guide covers the command on each platform, the flags that reveal the rest, and how to upgrade a version that is no longer supported.

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How to Generate a Self-Signed Certificate Using OpenSSL

A self-signed certificate is one you issue to yourself. No browser trusts it automatically, so it does not belong on a public website, but it is the quickest way to put HTTPS on a development or staging machine. This guide covers the command, the options worth changing, and how to make your own machine trust the certificate you created.

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How to Check the SSL Certificate Expiration Date with OpenSSL

Certificates issued after March 15, 2026 are capped at 200 days, and the limit drops again to 100 days in March 2027, so renewals come round far more often than they used to. Let one lapse and every visitor meets a full-page security warning. This guide covers checking the expiry date on a live server and in a local file, reading the output, and scripting the check so you are not tracking dates by hand.

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